For some time now, it has been the dream of the television set manufacturers to be able to commercially produce lightweight large screen TV systems. However, in view of the fact that the electronic components of such systems require an evacuated environment, it has not been possible to produce such a large lightweight flat panel TV system which could withstand the high atmospheric forces acting thereon. That is, when a relatively large shallow structure is evacuated, an atmospheric pressure of approximately one ton per square foot is exerted upon the enclosure structure, and if the base plate and face plate of such structure were each about eight square feet in area, then such plates would be subjected to a total atmospheric pressure of about sixteen tons. In order to produce a face plate of such size from television glass which could withstand such pressures without central support, it would be necessary to make the glass face plate approximately six inches thick, which of course would be completely absurd in view of the mass, weight and cost involved.
The use of supports in evacuated housings for supporting large panel areas is generally known in the art as shown by U.S. Pat. Nos. 3,995,615 and 4,038,965 pertaining to evacuated solar heat collectors. In U.S. Pat. No. 3,995,615, a plurality of posts project upwardly from the base to withstand the atmospheric pressure exerted on the transparent cover; whereas in U.S. Pat. No. 4,038,965, a plurality of load bearing partitions are proportioned and spaced so as to withstand pressure of more than one ton per square foot on the enclosure, the cover of which is of transparent material such as glass or clear plastic. It would appear from the drawings of both of the foregoing patents, that the structures thereof, including the posts and partitions, are made of a durable plastic, sealed at various intersecting joints to form a composite unit.
However, when attempts were made to heat seal a plurality of partitions or vanes within a flat glass plate panel TV system, so as to provide support for both the base plate and face plate thereof, it was found that the thermal gradients generated during the sealing of the vanes imposed an impossible stress on the structure causing breakage of the vanes and the structure. In view of the fact that the vanes were fixed to the base plate and not allowed to expand independently of the external housing structure, the stresses generated by the different expansion rates produced by the thermal gradients occasioned during the sealing cycle, produced catastrophic results in the breakage occurred within the vanes and between the vanes and the housing structure.
The present invention eliminates the problem of glass breakage occasioned in the sealing of fixed support vanes within a large flat panel TV structure by utilizing a plurality of floating vanes within such structure, which are fixtured therewithin in such a manner so as to permit limited movement during the sealing of the structure and to positively engage and support the base plate and face plate thereof when the structure is subjected to subatmospheric pressures.